Globaldocs allows you to conveniently browse multiple Javadoc sets
simultaneously, using a single packages/classes hierarchy tree and a
searchable index. It supports local and remote docsets, including the
local docsets, packed as JAR/ZIP-files.
Information regarding Project Releases and Project Resources. Note that the information here is a quote from Freecode.com page, and the downloads themselves may not be hosted on OSDN.
Full support of the JAR/ZIP archives that contain several docsets per archive was implemented. The ability to use several user-specified J2SE docsets was added. Some small improvements were made.